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SubjectRe: [PATCH 1/6] ARM: ks8695: watchdog: stop using mach/*.h
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Hi Arnd,

On 16/4/19 6:24 am, Arnd Bergmann wrote:
> drivers should not rely on machine specific headers but
> get their information from the platform device.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

I dug out some old ks8695 based hardware to try this out.
I had a lot of trouble getting anything modern working on it.
In the end I still don't have a reliable test bed to test this properly.

Your patch series works as well as the kernel before the changes,
so I am happy enough to ack them as they are.

Acked-by: Greg Ungerer <gerg@kernel.org>

Ultimately though I am left wondering if the ks8695 support in the
kernel is useful to anyone the way it is at the moment. With a minimal
kernel configuration I can boot up to a shell - but the system is
really unreliable if you try to interactively use it. I don't think
it is the hardware - it seems to run reliably with the old code
it has running from flash on it. I am only testing the new kernel,
running with the existing user space root filesystem on it (which
dates from 2004 :-)

Regards
Greg



> arch/arm/mach-ks8695/devices.c | 13 ++++++++++++-
> drivers/watchdog/Kconfig | 2 +-
> drivers/watchdog/ks8695_wdt.c | 30 +++++++++++++++++-------------
> 3 files changed, 30 insertions(+), 15 deletions(-)
>
> diff --git a/arch/arm/mach-ks8695/devices.c b/arch/arm/mach-ks8695/devices.c
> index 61cf20beb45f..57766817d86f 100644
> --- a/arch/arm/mach-ks8695/devices.c
> +++ b/arch/arm/mach-ks8695/devices.c
> @@ -169,11 +169,22 @@ void __init ks8696_add_device_hpna(void)
> /* --------------------------------------------------------------------
> * Watchdog
> * -------------------------------------------------------------------- */
> +#define KS8695_TMR_OFFSET (0xF0000 + 0xE400)
> +#define KS8695_TMR_PA (KS8695_IO_PA + KS8695_TMR_OFFSET)
> +static struct resource ks8695_wdt_resources[] = {
> + [0] = {
> + .name = "tmr",
> + .start = KS8695_TMR_PA,
> + .end = KS8695_TMR_PA + 0xf,
> + .flags = IORESOURCE_MEM,
> + },
> +};
>
> static struct platform_device ks8695_wdt_device = {
> .name = "ks8695_wdt",
> .id = -1,
> - .num_resources = 0,
> + .resource = ks8695_wdt_resources,
> + .num_resources = ARRAY_SIZE(ks8695_wdt_resources),
> };
>
> static void __init ks8695_add_device_watchdog(void)
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 242eea859637..046e01daef57 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -397,7 +397,7 @@ config IXP4XX_WATCHDOG
>
> config KS8695_WATCHDOG
> tristate "KS8695 watchdog"
> - depends on ARCH_KS8695
> + depends on ARCH_KS8695 || COMPILE_TEST
> help
> Watchdog timer embedded into KS8695 processor. This will reboot your
> system when the timeout is reached.
> diff --git a/drivers/watchdog/ks8695_wdt.c b/drivers/watchdog/ks8695_wdt.c
> index 1e41818a44bc..87c542c2f912 100644
> --- a/drivers/watchdog/ks8695_wdt.c
> +++ b/drivers/watchdog/ks8695_wdt.c
> @@ -23,10 +23,8 @@
> #include <linux/watchdog.h>
> #include <linux/io.h>
> #include <linux/uaccess.h>
> -#include <mach/hardware.h>
>
> -#define KS8695_TMR_OFFSET (0xF0000 + 0xE400)
> -#define KS8695_TMR_VA (KS8695_IO_VA + KS8695_TMR_OFFSET)
> +#define KS8695_CLOCK_RATE 25000000
>
> /*
> * Timer registers
> @@ -57,6 +55,7 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
>
> static unsigned long ks8695wdt_busy;
> static DEFINE_SPINLOCK(ks8695_lock);
> +static void __iomem *tmr_reg;
>
> /* ......................................................................... */
>
> @@ -69,8 +68,8 @@ static inline void ks8695_wdt_stop(void)
>
> spin_lock(&ks8695_lock);
> /* disable timer0 */
> - tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
> - __raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
> + tmcon = __raw_readl(tmr_reg + KS8695_TMCON);
> + __raw_writel(tmcon & ~TMCON_T0EN, tmr_reg + KS8695_TMCON);
> spin_unlock(&ks8695_lock);
> }
>
> @@ -84,15 +83,15 @@ static inline void ks8695_wdt_start(void)
>
> spin_lock(&ks8695_lock);
> /* disable timer0 */
> - tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
> - __raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
> + tmcon = __raw_readl(tmr_reg + KS8695_TMCON);
> + __raw_writel(tmcon & ~TMCON_T0EN, tmr_reg + KS8695_TMCON);
>
> /* program timer0 */
> - __raw_writel(tval | T0TC_WATCHDOG, KS8695_TMR_VA + KS8695_T0TC);
> + __raw_writel(tval | T0TC_WATCHDOG, tmr_reg + KS8695_T0TC);
>
> /* re-enable timer0 */
> - tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
> - __raw_writel(tmcon | TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
> + tmcon = __raw_readl(tmr_reg + KS8695_TMCON);
> + __raw_writel(tmcon | TMCON_T0EN, tmr_reg + KS8695_TMCON);
> spin_unlock(&ks8695_lock);
> }
>
> @@ -105,9 +104,9 @@ static inline void ks8695_wdt_reload(void)
>
> spin_lock(&ks8695_lock);
> /* disable, then re-enable timer0 */
> - tmcon = __raw_readl(KS8695_TMR_VA + KS8695_TMCON);
> - __raw_writel(tmcon & ~TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
> - __raw_writel(tmcon | TMCON_T0EN, KS8695_TMR_VA + KS8695_TMCON);
> + tmcon = __raw_readl(tmr_reg + KS8695_TMCON);
> + __raw_writel(tmcon & ~TMCON_T0EN, tmr_reg + KS8695_TMCON);
> + __raw_writel(tmcon | TMCON_T0EN, tmr_reg + KS8695_TMCON);
> spin_unlock(&ks8695_lock);
> }
>
> @@ -238,6 +237,11 @@ static struct miscdevice ks8695wdt_miscdev = {
> static int ks8695wdt_probe(struct platform_device *pdev)
> {
> int res;
> + struct resource *resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> + tmr_reg = devm_ioremap_resource(&pdev->dev, resource);
> + if (!tmr_reg)
> + return -ENXIO;
>
> if (ks8695wdt_miscdev.parent)
> return -EBUSY;
>

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